یہ ستم کس لیے اب خود پہ نہ ڈھایا جائے
دل سے وہ وعدہ فراموش بھلایا جائے
تلخ یادوں کو تلف کرنا ہے لازم ٹھہرا
ہر ورق مصحفِ ہستی کا جلایا جائے
Imm Ibn Taymiyyah is a well-known scholar of Muslims. He was an ocean of knowledge and wisdom. His books prove his excellence He was born in 661 Hijrah in Harrn (Syria). He learned every kind of knowledge especially religious knowledge i. E knowledge of Qur’n, Tafsr, Hadth, Fiqh, Jurisprudence, philosophy, inheritance law, mathematics, grammar, literature, and poetry etc. He wrote hundreds of books about the above mentioned fields. He was permitted to give Fatw (verdict) in his early age. He was successful in achieving the position of Ijtihd (authoritative interpretation of Islamic Law). Ibn Taymiyyah Studied the Profound Books of religions and sects. Then he analyzed the works in the light of senior Imams and Qurn and Sunnah. He is an extra ordinary person in his knowledge and writings. In brief we can say the fatws of Imam Ibn Taymiyyah have printed in thirty seven volumes. His first ratiocination in Fatwa is from the Holy Qurn. He presents the arguments from the Hadith and Sunnah of the Holy Prophet (S. A. W). He considered Ijm ‘ (consensus of Muslim opinion) as a proof of Shar‘ah. He presents the point of view of various schools of thought, He trusted in the books of ancient scholars. He also answers the anticipating ambiguity and complication. A few of his fatwas begin with all praise to Allah. His fatws are concordant with the life of the Muslims. In this article a deep study of fatwa of Ibn Taymiyyah has been taken as a guideline for fatwa in Islamic methodology.
The Radio Spectrum is used to transmit electromagnetic waves of different frequencies. With the passage of time people are getting aware of new technologies and as a result demand for different services has been increased. This results in the shortage of available spectrum. Spectrum utilization has now become a challenging task due to increase in wireless communications. Major licensed bands, such as those allocated for television broadcasting is not been fully utilized which results in spectrum wastage. This led to the idea of cognitive radio, first presented officially by Mitola and Maguire in 1999. Cognitive radio is a software-defined radio system, or SDR, a radio whose functionality is completely defined in software. Changes in SDR can be made by just changing the software. Mitola and Maguire proposed that the unused spectrum can be utilized by Secondary users (Unlicensed users) without creating harmful interference to Primary users (Licensed users). Secondary user can use the spectrum when primary user is inactive and should vacate the channel as soon as the primary user becomes active. An Efficient Signal Detection algorithm can perform this task. Detection of primary user signal is an elementary problem in cognitive radio. Energy detection, Match-filtering and Cyclostationary methods are widely used for spectrum sensing. This thesis will explore spectrum sensing methods and will analyze the performance of different techniques including methods based on the eigenvalue of the covariance matrix of received signals used as the test statistic. Different methods working with and without noise power will be simulated to demonstrate the performance of spectrum sensing techniques.